A little quick background.....I am prior military....was an armorer in the Army.....loved that job. As a civilian and approaching retirement I now hobby in building AR's and also I focus on long range shooting....I have a 6.5 Creedmoor precision rifle and a .338 lapua magnum precision rifle.....I can consistently shoot 1000 yards.....and I also love to build on the AR platform. My first build was a silenced .300aac SBR designed to shoot subsonic. I love it. I have also built a few 5.56 and .308. I have consistently shot at 960 yards with a .308 I built. I am a pretty good shooter, dedicated student, knowledgeable....and my passions for this run high. Not long ago I was also on FB in a couple of rifle forums. I had posted this beautiful 16" AR in .300AAC I had built.....it was designed to shoot supersonic rounds, to 400 yds - 500yds. The army lists the MER on this platform at 460 meters. I built it for fun. I can afford to. It operates so very well. It is fun..........And man I got TORCHED on that forum, like relentlessly. I was like....damn......torched for building a "dumb gun" that "was built for the exact opposite concept of the calibers design". I get it. I would bet money the monkey that made that statement has a 5.56mm AR pistol which of course is "the exact opposite concept of the calibers design"....but I get it. I am solid with my choices so I was not phased any.....taken back a bit maybe....because....damn. What did many folk do for a life prior to keyboard mouthiness? Any way......I would love to hear any thoughts on this subject. Even if I get torched.
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Can I get an opinion on .300aac......
- Thread starter SargeB
- Start date
For me. I don’t see any reason to have a long barreled 300. I like them shorter barreled because I run suppressors on them. I own a short barreled 223 wylde that I built as well to make it more maneuverable and I have a can for it. Those are my preferences. If you or anyone for that matter wants to build a 300 with a 16” barrel, do it. It’s your money. Enjoy it and your 2nd amendment. For people shitting on you about is pointless. And no need for it frankly. Btw, a 110 vmax is nasty in a 300 blk.
The real question is why are you on FB?
Maybe they just hated the lack of paragraphs. 
.300 blackout uses pretty fast burning powders so you’re probably not gonna gain a whole lot going the full 16” barrel. Mines 8” but I literally just built it as a range toy and I’m probably only gonna be running it suppressed with subs.
That being said, fuck em. It’s your money and your gun. If you like it, that’s literally all that matters. I’ve built multiple rifles just cus I felt like it and cus I thought it was cool or fun. I’m sure everyone else on here has too. And I’m also sure someone out there would talk shit about my build if they saw it. Guess who doesn’t give a damn. Lol
At the end of the day you built a functioning rifle that’s properly tuned and you’re proficient enough to run it. That’s more than most gun owners can say.
That being said, fuck em. It’s your money and your gun. If you like it, that’s literally all that matters. I’ve built multiple rifles just cus I felt like it and cus I thought it was cool or fun. I’m sure everyone else on here has too. And I’m also sure someone out there would talk shit about my build if they saw it. Guess who doesn’t give a damn. Lol
At the end of the day you built a functioning rifle that’s properly tuned and you’re proficient enough to run it. That’s more than most gun owners can say.
While it's not optimal, there are certainly arguments to be made for running a 300blk supers build.
First one that comes to mind for me is to take advantage of some of the more interesting opportunities in bullet construction vs 5.56
While if you want to shoot for range 5.56 is obviously superior to .300blk, the larger caliber of the bullets .300blk uses are much better suited to bullet constructions that can generate very devastating terminal effects, such as controlled fracturing and scored-jacket polymer tipped hollow points, particularly with solid bases. One example of this bullet type is the Lehigh Defense HVCQ bullets, which are designed to dump as much energy as possible while being completely barrier blind, a feat 5.56 has a very difficult time pulling off.
First one that comes to mind for me is to take advantage of some of the more interesting opportunities in bullet construction vs 5.56
While if you want to shoot for range 5.56 is obviously superior to .300blk, the larger caliber of the bullets .300blk uses are much better suited to bullet constructions that can generate very devastating terminal effects, such as controlled fracturing and scored-jacket polymer tipped hollow points, particularly with solid bases. One example of this bullet type is the Lehigh Defense HVCQ bullets, which are designed to dump as much energy as possible while being completely barrier blind, a feat 5.56 has a very difficult time pulling off.
They are retarded...
More or less the 300AAC, is an Americanized 7.62x39MM/9X39MM, It does really well out of short barrels, but when used out of shot out of longer barrels, carries similar performance as an full size AK with better bullet selection. 16 inch barrels that shoot a 30 cal bullet at 2300 to 2400fps are a thing that have done a lot of good work over the past 50 years.
It really depends on what you are going for at the end of the day.
For me, I could see a short, 300AAC replacing my 10.5, 556, but if I was a hunter, that extra 300 ft or so that a 16 inch barrel would be something nice to have in the back pocket over a short gun.
More or less the 300AAC, is an Americanized 7.62x39MM/9X39MM, It does really well out of short barrels, but when used out of shot out of longer barrels, carries similar performance as an full size AK with better bullet selection. 16 inch barrels that shoot a 30 cal bullet at 2300 to 2400fps are a thing that have done a lot of good work over the past 50 years.
It really depends on what you are going for at the end of the day.
For me, I could see a short, 300AAC replacing my 10.5, 556, but if I was a hunter, that extra 300 ft or so that a 16 inch barrel would be something nice to have in the back pocket over a short gun.
Very brave to get torched on FB and come to the Hide for an uplifting 
Nice rig you have there!
Here’s my 300 Blk. More of a range toy with subs.
Nice rig you have there!
Here’s my 300 Blk. More of a range toy with subs.
They are fun toys though,,,looks great!Very brave to get torched on FB and come to the Hide for an uplifting
Nice rig you have there!
Here’s my 300 Blk. More of a range toy with subs.
View attachment 7783299
Hornady 80873? I recently bought some and haver zeroed, have not put any down range yet!
This kind of thinking has been debunked for quite some time now. According to Mr Gun's N Gear's comprehensive testing going from a 9" barrel to a 16" barrel with 110-125 grain bullets you gain 250ish fps, or about 35fps per inch.
The truth is they are a bunch of little dicks. They simply do not know what they are talking about. Like with many things (especially in the gun world) people latch on to their 10% of the truth and will bitch at the other guy that talks about his 10%. They tend to operate under the mode of 'everyone is wrong but me'. Either that, or they are trying to act like some sort of gate keeper to the firearms world. They might be a gate keeper on their little internet forum but that certainly doesn't mean they know it all (despite what they think).
My FB experience is that anyone can be a self-proclaimed "expert" because they maintain a "page" and exspect anyone who joins their group to be obedient minions. Hurt their ego and they bump you out. I'll log on (at work, won't download it on my phone) just to see pics of grandkids. Have not posted anything on there in years. FMZ!
BLUF, FB is also known for it's "Freakin` Bozo's" 
...when 300BLK started up I built a 16"carbine, as that was the commonly available length you could get the barrels in at the time. @300M it had more "oomph" with 125gn projectiles on hanging plates than my 16" 556 slinging 77 SMK's. IMHO, not much difference between them in handling & performance.
...when shorter barrels became more readily available, I built a 10.1" "pistol". @300M using the same loads as for my 16", it is practically the same, not enough difference to be concerned about. Handling is totally different, much handier and is my preferred HD/CQB scenario tool. I doubt I'll ever get into any engagements @300M in this life now, but if I am unfortunate to find myself in that predicament, the 10.1" 300BLK pistol won't be a disadvantage if that's all I have and can't get to the other tools that are better suited and capable out to 1K.
...I've built 556 "pistols" in 7.5" & 10" configurations but found they did not have any performance or handling advantages over the 300BLK "pistol". In reality, they gave up more performance IMHO. About the only advantage for the .223/556 is common ammo and greater availability of it....but I reload so it's not an issue with availability or economics...
...when 300BLK started up I built a 16"carbine, as that was the commonly available length you could get the barrels in at the time. @300M it had more "oomph" with 125gn projectiles on hanging plates than my 16" 556 slinging 77 SMK's. IMHO, not much difference between them in handling & performance.
...when shorter barrels became more readily available, I built a 10.1" "pistol". @300M using the same loads as for my 16", it is practically the same, not enough difference to be concerned about. Handling is totally different, much handier and is my preferred HD/CQB scenario tool. I doubt I'll ever get into any engagements @300M in this life now, but if I am unfortunate to find myself in that predicament, the 10.1" 300BLK pistol won't be a disadvantage if that's all I have and can't get to the other tools that are better suited and capable out to 1K.
...I've built 556 "pistols" in 7.5" & 10" configurations but found they did not have any performance or handling advantages over the 300BLK "pistol". In reality, they gave up more performance IMHO. About the only advantage for the .223/556 is common ammo and greater availability of it....but I reload so it's not an issue with availability or economics...
16" is about the max I would build a blk.
It continues to increase velocity up to that length, but that is about the limit.
The advantage, of course, is that it is a rifle with a proper stock.
The only limit on it is commie states that prohibit semi-auto's, other that that, no paperwork, unless you are running a can and you don't have to worry about suddenly becoming a felon because your pistol is now declared an SBR.
Here is a printout comparing barrel lengths between blk and 55 grain 5.56.
the
It continues to increase velocity up to that length, but that is about the limit.
The advantage, of course, is that it is a rifle with a proper stock.
The only limit on it is commie states that prohibit semi-auto's, other that that, no paperwork, unless you are running a can and you don't have to worry about suddenly becoming a felon because your pistol is now declared an SBR.
Here is a printout comparing barrel lengths between blk and 55 grain 5.56.
300 blk gets dogged in favor of 5.56 by a lot by guys who just don't know -which is still a lot of people, somehow.
For 99.999% of users, subsonics are a novelty. If you have livestock/poultry and need to exterminate raccoons or coyotes or some nuisance animal quietly at night, it's a viable option. Outside of that, subsonics are firmly in mall ninja territory. And this is what most people run in 300 blk, so everybody thinks it doesn't have much real world utility.
But supersonics are an entirely different ballgame. Inside 500 yds, anything you'd use a 5.56 for, 300 blk supersonic will do with more energy, out of a much shorter barrel, with better terminal ballistics, and enormously better suppressability. The chart above by @fdkay spells it out pretty clearly. Honestly, I cannot figure out why anyone still buys ARs in 5.56.
For 99.999% of users, subsonics are a novelty. If you have livestock/poultry and need to exterminate raccoons or coyotes or some nuisance animal quietly at night, it's a viable option. Outside of that, subsonics are firmly in mall ninja territory. And this is what most people run in 300 blk, so everybody thinks it doesn't have much real world utility.
But supersonics are an entirely different ballgame. Inside 500 yds, anything you'd use a 5.56 for, 300 blk supersonic will do with more energy, out of a much shorter barrel, with better terminal ballistics, and enormously better suppressability. The chart above by @fdkay spells it out pretty clearly. Honestly, I cannot figure out why anyone still buys ARs in 5.56.
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Ammo dude. Not nearly as much .300 bo ammo on the market as 5.56 and it’s not exactly readily available. Not to mention more expensive.
That is an interesting chart though. I’ll have to load up some supers and try mine out at distance some time. Like you said mine is suppressed just a novelty. No real use case other than fun.
You are exactly correct, inside 500 yards. It always amazes me how the .300 rocks my steel targets
I have a few 300 blackout's and have killed several deer with super sonic and sub-sonic ammo . My Remington 700 has been a great shooting rifle . I bought a mini-14 300 blackout because It was easier to shoot subs than try to run 308 subs in my M1A . I have killed deer with all four .
My first 300blk build was with a 16” Wilson Combat barrel. Shoots great, kills deer well too.
Then I built an 8.5” and then 6”, both of which shoot great and kill deer well also.
I still have the 16” but haven’t shot it in a while as all of my hunting shots are close and I like the SBRs for suppressor use while still being maneuverable.
I chrono’d my 8.5 with Barnes 110 at 2105 fps and 6” at 1968 fps, so the chart from fdkay is pretty well spot on for my 8.5 and a bit conservative for my 6”. I think the minimum expansion for the Barnes is around the 1350 range so you still get decent range out of the SBRs
Any way you look at it, the 300blk is a cool round. As for the FaceF*#k flamers, who the heck are they to criticize you for building whatever you want?
ETA: I do shoot a decent amount of subs for fun, but haven’t hunted with them. They make for great low-noise plinking and are pretty accurate with the Hornady Sub-x 190 grain loads. Might have to go after a deer with these next year…
Then I built an 8.5” and then 6”, both of which shoot great and kill deer well also.
I still have the 16” but haven’t shot it in a while as all of my hunting shots are close and I like the SBRs for suppressor use while still being maneuverable.
I chrono’d my 8.5 with Barnes 110 at 2105 fps and 6” at 1968 fps, so the chart from fdkay is pretty well spot on for my 8.5 and a bit conservative for my 6”. I think the minimum expansion for the Barnes is around the 1350 range so you still get decent range out of the SBRs
Any way you look at it, the 300blk is a cool round. As for the FaceF*#k flamers, who the heck are they to criticize you for building whatever you want?
ETA: I do shoot a decent amount of subs for fun, but haven’t hunted with them. They make for great low-noise plinking and are pretty accurate with the Hornady Sub-x 190 grain loads. Might have to go after a deer with these next year…
That is a nice arrayI have a few 300 blackout's and have killed several deer with super sonic and sub-sonic ammo . My Remington 700 has been a great shooting rifle . I bought a mini-14 300 blackout because It was easier to shoot subs than try to run 308 subs in my M1A . I have killed deer with all four .
I use to shoot outlaw state 220 grain subs for deer hunting , but I started using the sub-x 190 grain when they come out . So far 3 shots and 3 dead deer . two dropped in their tracks and another run about 20 yds . I never shoot past 50-70 yds .
Your money, your build, your choices.
Sorry to hear FB is full of such open-minded folks... Lol
I have often considered a 16" barrel for my 300BK supers and hunting.... but haven't bought the 16" barrel based on other reports concerning the lack of meaningful velocity increases.... that might change.
Currently, I have a 10.5" barrel... originally it was 8.5", but IMHO there wasn't enough space on the handguard for my paws.
Enjoy your choices !!
Sorry to hear FB is full of such open-minded folks... Lol
I have often considered a 16" barrel for my 300BK supers and hunting.... but haven't bought the 16" barrel based on other reports concerning the lack of meaningful velocity increases.... that might change.
Currently, I have a 10.5" barrel... originally it was 8.5", but IMHO there wasn't enough space on the handguard for my paws.
Enjoy your choices !!
Most people with those opinions on 300BLK haven’t shot one for effect. It’s real fun to plink suppressed with no ears on with what sounds like a giant .22 - but supers are far more effective against game far farther out than subs.
Its a real reloaders caliber too. Not only are subs dirt cheap to reload (1/4 or less of factory prices), you can tune your super load to your longer barrel with a slower powder.
Nothing wrong with a 16, it just gets a little long with a can. I get the recent infatuation with super short guns (particularly once you add back on the length of a suppressor), but a 16” is far from unwieldy.
Its a real reloaders caliber too. Not only are subs dirt cheap to reload (1/4 or less of factory prices), you can tune your super load to your longer barrel with a slower powder.
Nothing wrong with a 16, it just gets a little long with a can. I get the recent infatuation with super short guns (particularly once you add back on the length of a suppressor), but a 16” is far from unwieldy.
The gun groups on Facebook are what drove me away from FB, specifically the precision rifle/PRS crowd.
The FB groups in that crowd are so amazingly cliquish and juvenile. It's an echo chamber of the same constant self gratification posts, and if you ever challenged any of their hivemind thoughts, you were quickly piled on.
It was a pretty unhealthy way to communicate and keep any semblance of a balanced perspective.
The FB groups in that crowd are so amazingly cliquish and juvenile. It's an echo chamber of the same constant self gratification posts, and if you ever challenged any of their hivemind thoughts, you were quickly piled on.
It was a pretty unhealthy way to communicate and keep any semblance of a balanced perspective.
I think the driving factor for that opinion is most likely cost of ammo to shoot it. It's mini action and effectively no different than 5.56 if you want to shoot medium distances accurately.
The big perk of 300blk is a lot of barrel burn in short barrel and staying subsonic. That's kind of the point it was designed. a 10" 300blk upper will sell much faster than a 16" 300blk upper because most people will see that as unnecessary and counterintuitive as to why you would want to shoot 300blk, and I'd tend to agree.
That would be similar to someone taking .375 cheytac and only using it at 50 yards. There's other setups that can achieve the same goal for much cheaper. HOWEVER, it would still probably be awesome. Same for your scenario.
The big perk of 300blk is a lot of barrel burn in short barrel and staying subsonic. That's kind of the point it was designed. a 10" 300blk upper will sell much faster than a 16" 300blk upper because most people will see that as unnecessary and counterintuitive as to why you would want to shoot 300blk, and I'd tend to agree.
That would be similar to someone taking .375 cheytac and only using it at 50 yards. There's other setups that can achieve the same goal for much cheaper. HOWEVER, it would still probably be awesome. Same for your scenario.
